How to use ListView.builder in flutter

To use ListView.builder in Flutter for creating dynamic and potentially long lists, follow these steps: Import the Material package.

Code

    import 'package:flutter/material.dart';

• Create a data source: This can be a List of strings, objects, or any data you want to display.

Code

    final List<String> items = List<String>.generate(100, (i) => 'Item $i');

• Implement ListView.builder within your build method:

Code

    class MyListViewScreen extends StatelessWidget {
      final List<String> items = List<String>.generate(100, (i) => 'Item $i');

      @override
      Widget build(BuildContext context) {
        return Scaffold(
          appBar: AppBar(
            title: const Text('ListView.builder Example'),
          ),
          body: ListView.builder(
            itemCount: items.length, // Required: Number of items in the list
            itemBuilder: (BuildContext context, int index) {
              // Required: Function to build each item
              return Card(
                margin: const EdgeInsets.all(8.0),
                child: ListTile(
                  leading: CircleAvatar(child: Text('${index + 1}')),
                  title: Text(items[index]),
                  subtitle: Text('Details for ${items[index]}'),
                  onTap: () {
                    // Handle item tap
                    print('Tapped on ${items[index]}');
                  },
                ),
              );
            },
          ),
        );
      }
    }

Explanation of key properties:

• itemCount: This required property specifies the total number of items in your list. It should be the length of your data source.
• itemBuilder: This is a required callback function that takes BuildContext context and int index as arguments. For each index from 0 to itemCount - 1, this function is called to build the widget for that specific item. You return the widget you want to display for each item in the list.

Benefits of ListView.builder:

• Performance: It builds items on demand, meaning only the widgets currently visible on screen (and a few extra for smooth scrolling) are rendered. This is highly efficient for large or infinite lists, as it avoids building all widgets at once.
• Dynamic Lists: It easily handles lists where the number of items can change dynamically.

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